How high does the temperature have to be for red ear slider turtles to dijest food ?

Answer 1

The temperatures aren't for them to diegest food, it's for them to survive (not freeze, eat, gain healthy shells, etc). The water needs to be between 70 and 75 degreese F and the basking area needs to be between 80 and 90 degreese F. The temp difference is essential so that they can warm up and cool down. They also need UVB lighting, which helps digest food. Without this you are poisoning your turtle. UVB produces vitamin d3 which prevents metabolic bone disease which leads to death, metabolizes d3 and metabolizes calcium, which without will kill your turtle. They also need UVA light/heat lamp.

Answer 2

Water temps should ideally be between 75-80F for best metabolism, although on a sunny day it can be cooler.